Download The TUNU-Programme: Euro-Arctic Marine Fishes—Diversity

Chapter 3
The TUNU-Programme: Euro-Arctic
Marine Fishes—Diversity and Adaptation
Jørgen S. Christiansen
3.1 Introduction
A firm focus on the scientific status, the vulnerability and the commercial potential
of the Arctic marine fishes is both timely and imperative. Parallel to the ongoing
and indisputable retreat of the Arctic summer sea ice (Comiso et al. 2008),
human activities increase rapidly into hitherto pristine parts of the Arctic Ocean:
petroleum exploitation has begun, commercial fisheries are developing, and
shipping routes across the Arctic Ocean are in operation with novel pollutants
such as antifouling, ballast water and noise in their wake. Grounds for particular
concern are marine bioprospecting, which eagerly extract commercially valuable
compounds from otherwise little known Arctic organisms.
The combination of climate and human stressors inevitably changes Arctic
marine ecosystems although the magnitude and outcome remains speculative.
In the light of ocean warming (Agustí et al. 2010) coming Arctic fisheries
will broadly affect two groups of fishes: harvested stocks found north of their
traditional distribution areas and non-target fishes native to Arctic waters. It is
worrying, therefore, to realise that there is a dearth of real biological data and
fundamental knowledge for the latter group of fishes. This is well illustrated by the
fact that 97% of the Arctic marine fish species are either data deficient (category
DD) or not evaluated (category NE) according to the criteria of the IUCN Red List.
The current state of Arctic marine fishes thus raises several key questions ripe for
scientific attention.
The ongoing TUNU-Programme at the University of Tromsø was coined 3
October 2002 during the PRE-TUNU-Expedition and became formally endorsed
J. S. Christiansen (&)
Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and Economics,
University of Tromsø, NO-9037 Tromsø, Norway
e-mail: [email protected]
G. di Prisco and C. Verde (eds.), Adaptation and Evolution in Marine Environments,
Volume 1, From Pole to Pole, DOI: 10.1007/978-3-642-27352-0_3,
Ó Springer-Verlag Berlin Heidelberg 2012
35
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J. S. Christiansen
by the International Polar Year (IPY, ID: 318) 25 May 2006. To date about 35
scientists and research students from 10 nations—Denmark, Finland, France,
Greenland, Iceland, Italy, Norway (Head), Russia, UK, USA—have been engaged
in the research activities.
The research programme addresses the diversity of species, populations and
communities of Arctic marine fishes in primarily Northeast Greenland (TUNU-MAFIG, see Sect. 3.3). Genetic and demographic structuring, trophic interactions and
physiological adaptations are viewed on a broad evolutionary time scale and in context
of novel climate and human stressors. A minor part of the research programme is
allocated studies on benthos and plankton communities as well as seal physiology.
The term ‘TUNU’ is etymologically ambiguous in modern Greenlandic—
geographically it refers to East Greenland and, anatomically, to the back or spine.
Both interpretations are adopted by the TUNU-Programme—the research activities began in Northeast Greenland with the ambition eventually to grow into a
scientific backbone in the study of Euro-Arctic marine fishes at large.
3.2 Arctic Fishes: Past, Present and Prospects
Sea ice is the most conspicuous element of the Arctic Ocean and the TUNUProgramme defines Arctic fishes as those species which are associated with iceladen seas at any time during their life cycle. Given this restriction, the assumed
number of genuine Arctic marine fish species presently known to science may
count about 60–70 (Mecklenburg et al. 2011).
3.2.1 Arctic Ichthyology in Retrospect
The roots of Arctic ichthyology can be ascribed to the eminent Danish priest (by
trade) and polyhistorian Otto Fabricius (Othonis Fabricii, 1744–1822). Equipped
with his volume of Systema Naturae (10th edition, Linnaeus 1758), Fabricius
initiated the study of the Arctic fauna and he was the first to develop a scientific
and annotated account on the Arctic fishes in his treatise Fauna Groenlandica
(1780, Fig. 3.1).
In this work, Fabricius described no less than 473 invertebrate and vertebrate
species of which he categorised 36 as Pisces and 9 cartilaginous fishes (Chondrichthyes) and lumpsuckers (Cyclopterus) as Amphibia [sic]. Altogether, Fauna
Groenlandica contains comprehensive descriptions of 45 fish species. Several of
Fabricius’ descriptions of the approximately 130 species new to science, however,
were published a few years earlier in Zoologiae Danicae Prodomus (1776) by his
contemporary countryman, the renowned zoologist OF Müller (1730–1784).
Fabricius is unquestionably a pioneer of Arctic zoology and many of his scientific
contributions are still valid (Kapel 2005). Moreover, Fabricius broke new grounds
during his stay in West Greenland (Paamiut district, 1768–1773), since he fully
3 The TUNU-Programme: Euro-Arctic Marine Fishes
37
Fig. 3.1 O Fabricius (1744–1822) and the front page of his Fauna Groenlandica (1780)
appreciated the value of and extensively employed traditional ecological knowledge (TEK) in his scientific work (Jensen 1923). Prominent ichthyologists of the
nineteenth and the first half of the twentieth century, mainly from Denmark (CF
Lütken, 1827–1901, and Ad S Jensen, 1866–1953), Russia and the Soviet Union
(LS Berg, 1876–1950, GU Lindberg, 1894–1976, AN Svetovidov, 1903–1985, and
AP Andriashev, 1910–2009), invigorated Fabricius’ work and developed the
classification and zoogeographic knowledge of Arctic fishes even further.
3.2.2 Problems and Prospects for Arctic Ichthyology
Despite the effort of outstanding ichthyologists, knowledge of the Arctic fish
fauna remains sparse compared to for example the Antarctic marine fauna which
has been extensively studied for decades (Piepenburg 2008). Besides logistic
constraints, the most serious hindrance towards a comprehensive understanding of
Arctic marine biodiversity lies in the fact that our information, by and large, is
qualitative (presence-absence) and based on random and fragmentary snapshots
accumulated over periods of time revealing no coherent time series.
The Arctic societies are by far based on living natural resources and the
socio-economic progress is inevitably rooted in sound ecosystems. Forecasts of
biological responses to climate change require multifaceted actions and empirical
gaps can hardly be bridged solely by sophisticated models and unsubstantiated
hypotheses. Lack of real data presently represents the most severe shortcoming for
a reliable assessment and, ultimately, a sustainable management of the Arctic seas.
The scientific rationale behind the TUNU-Programme, therefore, is to advance the
biological knowledge of the Euro-Arctic marine fish faunae at large.
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3.3 The TUNU-Programme: Structure and Function
3.3.1 The Study Area
A clear-cut definition of the marine Arctic has yet to be developed. One definition
simply includes the seas within the Arctic Circle, e.g. AMAP (Arctic Monitoring
and Assessment Programme), whereas others are based on major zoogeographic
shifts in the fish fauna (Mecklenburg et al. 2011). Geographic boundaries are static
and have little ecological meaning. More importantly, they do not account for
the ongoing changes in the Arctic sea ice cover and quality, i.e. the decrease in the
perennial to annual sea ice ratio (Walsh 2008).
In context of the TUNU-Programme, we define the marine Euro-Arctic as the
fjords, shelves and slopes (\1,500 m) associated with the maximum extent of the
sea ice cover (usually in March). That embraces areas which are seasonally
affected by the Fast Ice in the fjords and the drifting Pack Ice covering the shelves
(Pickard and Emery 1990). This definition introduces a needed dynamic and
meaningful ecological dimension to the marine Arctic and inevitably reflects both
the temporal variations in sea ice cover and the concomitant responses of the fish
faunae.
The geographic area of attention in the TUNU-Programme was initially
restricted to the fjords and shelf-slope areas in Northeast Greenland (TUNUMAFIG). Recently the research area is expanded also to include the marine fish
faunae across the entire Euro-Arctic triangle, i.e. from west to east: Northeast
Greenland (Arctic water) via Jan Mayen Island (Arctic and Atlantic waters),
Svalbard Archipelago (Atlantic and Arctic waters) and, whenever feasible,
towards the Franz Joseph Land Archipelago (Arctic water). Those Arctic sites are
bordering the Atlantic Arctic Gateway, i.e. the Norwegian Sea and the Barents
Sea, and are considered exceptionally appropriate for comparative marine biological studies. They share similar photoperiods (latitudes) but are affected by
completely different water masses, thermal conditions and invasion histories
(Fig. 3.2).
Larger parts of the Euro-Arctic region are marine protected areas (MPAs) and
strict admission permits are required from the respective authorities in Greenland,
Norway and Russia. Thus, most studies in the TUNU-Programme have been
carried out within the borders of the Northeast Greenland National Park which is
the largest in the world (972,000 km2).
3.3.2 The TUNU Expeditions
The logistic backbone of the TUNU-Programme consists of regular expeditions
with the ice strengthened R/V Jan Mayen headed by the University of Tromsø
(Table 3.1, Fig. 3.3).
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39
Fig. 3.2 Geographic coverage of the TUNU-Programme. The core areas of investigation are
encircled: Northeast Greenland (TUNU-MAFIG, green), Jan Mayen Island (black) and the
Svalbard Archipelago (red). The Franz Joseph Land Archipelago is included as a prospect
comparative reference site (dashed). The arrows indicate the major Arctic (blue) and Atlantic
(red) surface currents
Seven expeditions were conducted successfully in autumns 2002 (PRE-TUNU),
2003 (TUNU-I), 2005 (TUNU-II), 2007 (TUNU-III), summers 2008 (TUNU-Seal)
and 2010 (TUNU-IV), and winter 2011 (TUNU-SVAL I). During the TUNU
Expeditions, series of biological and hydrographic stations and transects are
identified in primarily Northeast Greenland waters (see Sect. 3.3.3). Three expeditions had logistic and scientific collaboration with national research institutions,
i.e. Institute of Marine Research and the Dept. of Geology, University of Tromsø.
Two PhD courses in Arctic marine biology were carried out in 2005 and 2010
under the auspices of the ARCTOS PhD-School, University of Tromsø, and two
PolART performers in visual arts participated in 2008.
3.3.3 Stations and Sampling Procedures
To date, 235 stations in toto are covered during the TUNU Expeditions with 170
stations in Northeast Greenland, 30 at Jan Mayen Island, and 35 at Svalbard
Archipelago (Table 3.1). The stations embrace habitats from the littoral zone in the
innermost parts of the fjords via the shelves to the continental slope (\1,500 m)
(Fig. 3.4). Together the stations provide first hand quantitative data and meta-data on
inter-annual variations in fish faunae and concurrent hydrographic regimes.
An array of sampling methods is employed during the TUNU Expeditions
(Fig. 3.5) although sampling was strongly hampered by exceptionally heavy sea
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J. S. Christiansen
Table 3.1 Overview of completed TUNU Expeditions and the number of stations examined
(N = 235 in toto) during the period 2002–2011
Expeditions
Date
Study area
Stations
Comments
PRE-TUNU
TUNU-I
TUNU-II
TUNU-III
TUNU-Seal
TUNU-IV
TUNU-SVAL I
25
02
26
29
29
06
17
Sep-18 Oct 2002
Oct-13 Oct 2003
Sep-10 Oct 2005
Sep-12 Oct 2007
Jun-12 Jul 2008
Aug-17 Aug 2010
Jan-25 Jan 2011
NEG and
NEG and
NEG
NEG and
JMI
NEG and
SVAL
SVAL
JMI
SVAL
SVAL
38
50
36
33
28
33
17
IMR
PhD-School
DG
IMR & PA
PhD-School
NEG Northeast Greenland, JMI Jan Mayen Island, SVAL Svalbard Archipelago, IMR Institute
of Marine Research, DG Dept. of Geology, PA PolART performers
Fig. 3.3 The R/V Jan Mayen in Scoresby Sund Fjord (*70°N), Northeast Greenland, October
2007. On the 17 June 2011, the R/V Jan Mayen was renamed R/V Helmer Hanssen. Helmer
Hanssen (1870, Bjørnskinn-1956, Tromsø) was a polar explorer who participated in three famous
expeditions headed by Roald Amundsen: The Gjøa expedition through the Northwest passage
(1903–1906), the Fram expedition to the South pole (1911), and the Maud expedition through the
Northeast passage (1918–1920)
ice in 2005 and 2007 (Fig. 3.4). Arctic fishes are by far bottom dwelling (Fig. 3.6)
and standardized bottom trawls, Campelen Super 1800/96 NOFI, are employed as
the main gear for quantitative studies of fish diversity. Whenever required, additional live fishes are sampled at the same sites for experimental studies onboard the
R/V Jan Mayen. Fish diversity stations (N = 83) include complementary data on
echo-sounding, trawl gear dimensions and speed, and measurements of in situ
depth and temperature. Profiles of hydrography and chlorophyll are obtained by
CTD-sensors at the same sites as fish sampling (N = 91) and water samples across
the entire Northeast Atlantic were obtained in 2005. All fishes are identified
to species, counted and weighed. Fresh voucher specimens are labelled,
photographed and frozen whole for the TUNU Museum Collection (TMC, see
Sect. 3.3.4.4).
3 The TUNU-Programme: Euro-Arctic Marine Fishes
41
Fig. 3.4 Stations for quantitative studies of fish diversity in Northeast Greenland (N = 56)
between latitudes *70–78°N (2002–2010), cf. Fig. 3.2. The satellite photo shows the pack ice
(Greenlandic–‘Sikorsuit’) between latitudes *70–74°N, 4 October 2007 (Courtesy:
www.seaice.dk). The drifting ‘Sikorsuit’ in Northeast Greenland is an exceptional marine ecosystem which deserves a research programme of its own
Observations of birds and sea mammals are made regularly during all TUNU
Expeditions and they were carried out systematically in 2008 and 2010 (Byrkjedal
and Madsen 2008).
3.3.4 Scientific Foci
It is generally assumed that the Arctic marine fish fauna was established relatively
recently (2–3 million years ago, mya) compared to its counterpart in the Southern
Ocean, Antarctica, which may have evolved under cold environmental conditions for
the past 10–17 mya (DeVries and Steffensen 2005; Patarnello et al. 2011). Interestingly, a recent study on ocean floor sediments suggests that the modern circulation
in the Arctic Ocean actually dates back about 17 mya and a perennial sea ice cover
was formed about 13 mya (Krylov et al. 2008). Given this perspective, Arctic and
Antarctic regions display a coeval freeze and the polar faunae should be viewed on
the same geological time scale. However, this may not affect our current perception
of polar fish evolution in view of the fact that the Arctic and Antarctic regions differ
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Number of stations
100
Svalbard
Jan Mayen Island
NE Greenland
75
50
25
Loggers
Drift buoys
Agassiz
Beach seine
Fish traps
Long line
Van Veen
WP2
Diving
Tucker
Campelen
CTD
0
Sampling methods
Fig. 3.5 Sampling methods employed at 235 stations in Northeast Greenland, Jan Mayen Island
and Svalbard Archipelago, 2002–2011. CTD = hydrography, Campelen = bottom trawl, Tucker
and WP2 = zooplankton, Van Veen = sediments, Agassiz = macro-benthos
Boreal: 11%
Spatial habitat
Cryo-pelagic
Arctic: 61%
Pelagic
Arctic-Boreal:
28%
Bathy-pelagic
Benthic
0
10
20
30
40
50
60
70
80
90
Proportion of NE Greenland fishes (%)
Fig. 3.6 Functional diversity. Spatial habitat and zoogeographic affiliation (inserted pie chart)
for the Northeast Greenland fish species (cf. Table 3.2)
significantly in invasion history, biogeographic isolation and environmental
stability. Bipolar comparisons, therefore, are particularly valuable to grasp the
evolutionary history and prospects of Arctic fishes and several participants in
the TUNU-Programme are studying the fish faunae in both polar hemispheres. The
TUNU-Programme is broadly organised into four research activities:
3 The TUNU-Programme: Euro-Arctic Marine Fishes
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Table 3.2 Preliminary checklist of the fish species encountered in Northeast Greenland,
2002–2010. Phylogenetic order and family numbering follows Nelson (2006). The inserted
emblem represents the research activities in Northeast Greenland (TUNU-MAFIG)
FISHES OF NORTHEAST GREENLAND
2002-2010
CLASS ELASMOBRANCHII
Family 37. SOMNIOSIDAE (sleeper sharks)
Somniosus microcephalus Bloch-Scheider 1801
Family 48. RAJIDAE (skates)
Amblyraja hyperborea Collett 1879
Amblyraja radiata Donovan 1808
CLASS ACTINOPTERYGII
Family 172. OSMERIDAE (smelts)
Mallotus villosus Müller 1776
Family 200. MYCTOPHIDAE (lanternfishes)
Benthosema glaciale Reinhardt 1837
Family 219. PHYCIDAE (phycid hakes)
Gaidropsarus argentatus Reinhardt 1837
Family 220. GADIDAE (codfishes)
Arctogadus glacialis Peters 1872
Boreogadus saida Lepechin 1774
Gadus morhua Linnaeus 1758
Family 291. GASTEROSTEIDAE (sticklebacks)
Gasterosteus aculeatus Linnaeus 1758
Family 304. SCORPAENIDAE (scorpionfishes
or rockfishes)
Sebastes mentella Travin 1951
Sebastes norvegicus Ascanius 1772
Family 320. COTTIDAE (sculpins)
Artediellus atlanticus Jordan-Evermann 1898
Gymnocanthus tricuspis Reinhardt 1831
Icelusbicornis Reinhardt 1840
Myoxocephalus scorpius Linnaeus 1758
Myoxocephalus quadricornis Linnaeus 1758
Triglops nybelini Jensen 1944
Triglops pingeli Reinhardt 1831
Family 324. AGONIDAE (poachers)
Leptagonus decagonus Bloch-Scheider 1801
Family 325. PSYCHROLUTIDAE (fathead
sculpins)
Cottunculus microps Collett 1875
Cottunculus sadko Esipov 1937
Psychrolutes subspinosus Jensen 1902
Family 327. CYCLOPTERIDAE
(lumpfishes or lumpsuckers)
Eumicrotremus spinosus Fabricius 1776
Family 328. LIPARIDAE (snailfishes)
Careproctus idet.
Careproctus micropus Günther 1887
Careproctus see reinhardti Krøyer 1862
Liparis fabricii Krøyer 1847
Liparis gibbus Bean 1881
Liparis tunicatus Reinhardt 1837
Paraliparis bathybius Collett 1879
Rhodichthys regina Collett 1879
Family 416. ZOARCIDAE (eelpouts)
Gymnelus retrodorsalis Le Danois 1913
Lycenchelys kolthoffi Jensen 1904
Lycenchelysmuraena Collett 1878
Lycodes eudipleurostictus Jensen 1902
Lycodes paamiuti Møller 2001
Lycodes pallidus Collett 1879
Lycodes polaris Sabine 1824
Lycodes reticulatus Reinhardt 1835
Lycodes rossi Malmgren 1865
Lycodes seminudus Reinhardt 1837
Lycodes squamiventer Jensen 1902
Lycodonus flagellicauda Jensen 1902
Family 417. STICHAEIDAE
(pricklebacks)
Leptoclinus maculatus Fries 1838
Family 493. PLEURONECTIDAE
(righteye flounders)
Hippoglossoides platessoides Fabricius
1780
Reinhardtius hippoglossoides Walbaum
1792
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3.3.4.1 Taxonomy, Distribution and Diversity
The taxonomy of Arctic marine fishes is both complex and controversial and,
in light of the molecular revolution, several genera are ripe for major revisions
(Mecklenburg et al. 2011). Barcoding of mtDNA and nDNA microsatellites
have become major tools for identification of fish taxa and populations (Ward
et al. 2009) but molecular techniques are no substitute to morphological studies.
For example, strong intra-specific phenotypic variations exist (Byrkjedal et al.
2007) and the combination of classic taxonomy (phenotypic plasticity) and
molecular studies (the underlying genotype) will provide not only information
but also knowledge on the evolution of Arctic marine fishes (Naish and Hard
2008).
The term ‘distribution’ is ambiguous and we may distinguish between zoogeographic patterns and phylogeographic processes of fish distribution. Whereas
zoogeography simply provides the total spatial range for a given taxon (i.e. the
pattern), phylogeography reflects the origin, evolutionary history and the putative
dispersal routes of taxa through space and time (i.e. the underlying processes).
Obviously, the study of phylogeography is much more multifaceted and requires
ample information both on the genetic lineages among fish taxa and populations
and the temporal dynamics in environmental barriers that give rise to certain
zoogeographic patterns (Briggs 1974; Hardy et al. 2011). The study of marine
fish distribution within the Euro-Arctic region is of particular actuality due to
ocean warming and a concomitant northward shift in the geographic range
for a number of boreal species in recent years (Perry et al. 2005; Wienerroither
et al. 2011).
Polar seas are usually considered species poor compared to lower latitudes.
Recent investigations of marine invertebrates in the Southern Ocean, however,
reveal a much higher biodiversity than previously thought (Brandt et al. 2007).
The bottom topography in Northeast Greenland is often massively disturbed by
moving icebergs and together with the pack ice this poses several logistic
problems for sampling (Figs. 3.3 and 3.4). Thus, the numbers of Arctic fish
species are either underestimated (i.e. apparent) due to inadequate sampling
and/or taxonomic controversies or a biological reality of unknown causes (cf.
the idea of ‘‘dark diversity’’ by Pärtel et al. 2011). This clearly calls for further
scientific attention.
3.3.4.2 Functional Ecology
Due to environmental constraints such as subzero temperature and seasonal food
shortage, Arctic marine fishes are thought to grow and reproduce slowly but
even fundamental data on demographic structuring (e.g. Von Bertalanffy
Growth Functions), longevity, life history and trophic status are lacking. Trophic
interactions inferred from stable isotope profiles and stomach analyses are coupled
with studies of pollutants within species (bioaccumulation) and food chains
3 The TUNU-Programme: Euro-Arctic Marine Fishes
45
(biomagnification) as well as parasites (Køie et al. 2007). Moreover, most
Arctic marine fish species are bottom dwelling and substrate spawners (Fig. 3.6,
Christiansen et al. 1998). This would make them particularly vulnerable as unwarranted by-catch and to habitat destruction caused by conventional trawl gears.
3.3.4.3 Thermal Adaptation and Evolution
Polar fishes (Arctic and Antarctic) have evolved an array of exceptional physiological and biochemical adaptations to tackle ice-laden seas (DeVries and Cheng
2005; di Prisco and Verde 2006). This may have resulted in loss of genetic variability at adaptive loci and a limited capacity to overcome novel stressors such as
ocean warming (Patarnello et al. 2011). Polar marine fishes are assumed to be
extremely temperature sensitive and stenothermal and they display a clear structuring in thermal distribution even within the narrow temperature zone encountered in polar waters. Moreover, physiological key properties in polar fishes may
show a sharp curvilinear response by a change from subzero to positive ambient
temperatures (Christiansen et al. 1995). For this reason, even a slight rise in sea
temperature may have disproportionally large consequences for the overall fitness
of polar fishes compared to lower latitude counterparts.
One of the most striking features of polar fishes is their ability to tolerate nearfreezing temperatures by means of antifreeze peptides and glycoproteins in tissues
and body fluids (DeVries and Cheng 2005). On the other hand, effects of high
temperature in polar fishes are much less understood (Hofmann et al. 2000;
Bilyk and DeVries 2011) although the Arctic gadoid Boreogadus saida may
tolerate laboratory temperatures of *14°C for weeks (Christiansen et al. 1997)
and appears to display an intermediate thermal stress response between that of
Antarctic and temperate fishes (Whiteley et al. 2006). Studies of whole body
metabolism in polar fishes reveal no adaptation to low temperatures (Steffensen
2005), whereas respiratory proteins such as hemoglobins (Hbs) show distinct
adaptations to polar environments (Verde et al. 2006, 2012). Fishes devoid of Hbs,
however, are yet not known from the Arctic Ocean cf. the Hb-less icefishes
Channichthyidae in the Southern Ocean (di Prisco et al. 2002).
3.3.4.4 The TUNU Museum Collection
Natural History collections hold important information to reconstruct long-term
data series (Harrison et al. 2011; Lister et al. 2011) and voucher specimens from
the TUNU Expeditions are collected systematically for the TUNU Museum
Collection (TMC, c/o Senior Curator I Byrkjedal) at Bergen Museum. The TMC
contains pro tem about 650 voucher specimens from 47 species for further taxonomic studies and corresponding tissues are fixed in ethanol for phylogenetic
validation.
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3.3.5 Fishes in Northeast Greenland
To date, 3 cartilaginous fish species in 3 families and 44 bony fish species in 14
families are identified from Northeast Greenland during the TUNU Expeditions
(Table 3.2). The species encountered are all marine but the diadrome stickleback
Gasterosteus aculeatus. The diadrome Arctic charr Salvelinus alpinus is indeed
numerous in the fjords of Northeast Greenland but they return to freshwaters
in early summer and were absent at sea at the time of the TUNU Expeditions in
August-October.
The Arctic marine fishes are taxonomically complex and further analyses are
needed, particularly within the speciose, sensu Hart (2008), families Cottidae,
Liparidae, and Zoarcidae.
The spatial habitat and zoogeographic affiliation of the Northeast Greenland
fishes are shown in Fig. 3.6. More than 85% of the species display a benthic life style
and only two are considered cryo-pelagic, sensu Andriashev (1970), as they utilize
the sea ice as feeding grounds, refuge and spawning substrate (see Sect. 3.3.6).
More than 60% of the species are considered genuinely Arctic and spawn
mainly at subzero temperatures. On the other hand, 11% are boreal and spawn
solely at positive ambient temperatures (Mecklenburg et al. 2011). In the light of
ocean warming, the number and proportion of pelagic and boreal species (Fig. 3.6)
is expected to increase in the Euro-Arctic region (Wienerroither et al. 2011).
3.3.6 Arctic Codfishes and How (Not) to Name Them
Two cryo-pelagic gadoids (family Gadidae) are endemic to the Arctic Ocean with
each genus being represented by only a single species: Arctogadus glacialis and
Boreogadus saida (Table 3.2, Fig. 3.7). The B. saida is beyond doubt an Arctic
key-stone species both in terms of abundance and ecological significance and
being the northernmost occurring fish species it is widespread throughout the
Arctic Seas (Christiansen and Fevolden 2000; Christiansen et al. 2010 and references therein). The A. glacialis, on the other hand, is much less abundant and it is
primarily associated with the Arctic fjords and shelves (Aschan et al. 2009). The
two species are taxonomically distinguished by simple phenotypic features for
adults (Fig. 3.7) and genetic markers for the larval stages (Madsen et al. 2009).
The scientific nomenclature is unsurpassed to vernacular names in scientific
communication. There are several unfortunate examples from the scientific literature where the identification of these Arctic codfishes is mixed up due to lack of
consistency in the use of vernacular names. Hence, B. saida is known both as
‘Polar cod’ and ‘Arctic cod’ and vice versa for A. glacialis. To add further confusion, the migrating population of Atlantic cod Gadus morhua (Norwegian–skrei)
is also known as ‘Northeast Arctic cod’ by ICES (International Council of
Exploration of the Seas) and it has been mistaken for B. saida.
3 The TUNU-Programme: Euro-Arctic Marine Fishes
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Fig. 3.7 Endemic gadoids of the Arctic Ocean—the cryo-pelagic ‘Polar cod’ and ‘Ice cod’
The scientific name is conclusive and should always follow the vernacular
name for these species. The vernacular names ‘Ice cod’ for Arctogadus glacialis
and ‘Polar cod’ for Boreogadus saida are employed by the TUNU-Programme.
3.4 Dissemination and Communication
The TUNU-Programme has communicated results in various ways both to the
general public and the scientific community. Thus far, studies are mainly published
within the fields of thermal adaptation and genetics. Studies combining quantitative fish diversity and the physical environment are presently being undertaken to
examine inter-annual variations and putative trends since 2002. The scientific
communication comprises: Technical Expedition Reports (TERs), peer-reviewed
scientific journals, popular science, MSc and PhD theses, internal workshops and
international conferences. In addition, international courses for PhD-students and
young scientists are given during selected expeditions. Live Arctic fishes are
collected regularly for display at the public aquarium (POLARIA) in Tromsø
and an art exhibition was presented by PolART at the Tromsø Art Society in 2009.
A web-site with general information, dissemination and access to meta-data from
the TUNU Expeditions is planned operative from spring 2012.
The TUNU-Programme is affiliated with CAFF (Conservation of Arctic Flora
and Fauna), the IUCN Redlist (International Union for Conservation of Nature),
the EU COST-Action: Conservation Physiology of Marine Fishes, EBA (Evolution
and Biodiversity in Antarctica), and the ARCTOS network at the University of
Tromsø.
3.5 Prospects for the TUNU-Programme
Basic transects for long-term monitoring and studies on ocean climate and the
marine fish faunae are now established in Northeast Greenland and key-stations are
adopted by CBMP (Circumpolar Biodiversity Monitoring Program) commissioned
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by CAFF. More investigations are needed in the littoral zone and in deep waters
([1,500 m) and an array of gears such as beach seines, traps and long lines should be
employed to a larger extend to cover also difficult and little accessible habitats.
Studies on the fish fauna during the Arctic winter are practically absent and coming
TUNU Expeditions should emphasise this issue to discriminate between seasonal
and resident fish species (cf. TUNU-SVAL I, Table 3.1).
The TUNU-Programme was initially confined to Northeast Greenland
(TUNU-MAFIG: MArine FIshes of NE Greenland—Diversity and Adaptation).
With the expanded TUNU-Programme: Euro-Arctic Marine Fishes—Diversity
and Adaptation (acronym: TEAM-Fish), we aim to continue our work also in the
remaining parts of the Euro-Arctic region.
Acknowledgements I sincerely thank the members of the TUNU-Programme, the crew onboard
the R/V Jan Mayen, and the Government of Greenland. I further thank G. di Prisco and C. Verde
for the opportunity to write this summary, F. Strand for preparation of maps, M. Jobling for useful
references, and S. Adams at Blå Rock for suitable working conditions.
References
Agustí S, Sejr MK, Duarte CM (2010) Impacts of climate warming on polar marine and
freshwater ecosystems. Polar Biol 33:1595–1598
Andriashev AP (1970) Cryopelagic fishes of the Arctic and Antarctic and their significance in polar
ecosystems. In: Holdgate MW (ed) Antarctic ecology. Academic, New York, pp 297–304
Aschan M, Karamushko OV, Byrkjedal I, Wienerroither R, Borkin I, Christiansen JS (2009)
Records of the gadoid fish Arctogadus glacialis (Peters, 1814) in the European Arctic. Polar
Biol 32:963–970
Bilyk KT, DeVries AL (2011) Heat tolerance and its plasticity in Antarctic fishes. Comp
Biochem Physiol A 158:382–390
Briggs JC (1974) Operation of zoogeographic barriers. Syst Zool 23:248–256
Brandt A, Gooday AJ, Brandão SN et al (2007) First insights into the biodiversity and
biogeography of the Southern Ocean deep sea. Nature 447:307–311
Byrkjedal I, Madsen J (2008) Autumn bird observations in the Northeast Greenland sea ice.
Dansk Orn Foren Tidsskr 102:325–330
Byrkjedal I, Rees DJ, Willassen E (2007) Lumping lumpsuckers: molecular and morphological
insights into taxonomic status of Eumicrotremus spinosus (Fabricius 1776) and Eumicrotremus
eggvinii Koefoed, 1956 (teleostei: cyclopteridae). J Fish Biol 71:111–131
Christiansen JS, Fevolden S-E (2000) The polar cod of Porsangerfjorden, Norway; revisited.
Sarsia 85:189–193
Christiansen JS, Chernitsky AG, Karamushko OV (1995) An Arctic teleost with a noticeably high
body fluid osmolality—a note on the navaga, Eleginus navaga (Pallas 1811), from the white
sea. Polar Biol 15:303–306
Christiansen JS, Karamushko LI, Nahrgang J (2010) Sub-lethal levels of waterborne petroleum
may depress routine metabolism in polar cod Boreogadus saida (Lepechin, 1774). Polar Biol
33:1049–1055
Christiansen JS, Schurmann H, Karamushko LI (1997) Thermal behaviour of polar fish: a brief
survey and suggestions for research. Cybium 21:353–362
Christiansen JS, Fevolden S-E, Karamushko OV, Karamushko LI (1998) Maternal output in polar
fish reproduction. In: di Prisco G, Pisano E, Clarke A (eds) Fishes of Antarctica, a biological
overview. Springer, New York, pp 41–52
3 The TUNU-Programme: Euro-Arctic Marine Fishes
49
Comiso JC, Parkinson CL, Gersten R, Stock L (2008) Accelerated decline in the Arctic sea ice
cover. Geophys Res Lett. doi:10.1029/2007GL031972
DeVries AL, Cheng C-HC (2005) Antifreeze proteins and organismal freezing avoidance in polar
fishes. In: Farrell AP, Steffensen JF (eds) The physiology of polar fishes. Academic, New York,
pp 155–201
DeVries AL, Steffensen JF (2005) The Arctic and Antarctic polar marine environments. In:
Farrell AP, Steffensen JF (eds) The physiology of polar fishes. Academic, New York, pp 1–24
di Prisco G, Verde C (2006) Predicting the impacts of climate change on the evolutionary
adaptations of polar fish. Rev Environ Sci Biotech 5:309–321
di Prisco G, Cocca E, Parker SK, Detrich HW III (2002) Tracking the evolutionary loss of
hemoglobin expression by the white-blooded Antarctic icefishes. Gene 295:185–191
Fabricius O (1780) Faunae groenlandica. http://www.archive.org/details/ faunagroenlandi 00fabrgoog
Hardy SM, Carr CM, Hardman M, Steinke D, Corstorphine E, Mah C (2011) Biodiversity and
phylogeography of Arctic marine fauna: insights from molecular tools. Mar Biodiv 41:195–210
Harrison IJ, Chakrabarty P, Freyhof J, Craig JF (2011) Correct nomenclature and recommendations for preserving and cataloguing voucher material and genetic sequences. J Fish Biol
78:1283–1290
Hart MW (2008) Speciose versus species-rich. TREE 23:660–661
Hofmann GE, Buckley BA, Airaksinen S, Keen JE, Somero GN (2000) Heat-shock protein
expression is absent in the Antarctic fish Trematomus bernacchii (family nototheniidae).
J Exp Biol 203:2331–2339
Jensen AdS (1923) Naturforskeren Otto Fabricius. Meddelelser om Grønland 42:331–399 (in
Danish)
Kapel FO (2005) Otto Fabricius and the seals of Greenland. Meddelelser om Grønland, Biosci
55:1–150
Køie M, Steffensen JF, Møller PR, Christiansen JS (2007) Parasite fauna of Arctogadus glacialis
(Peters) (Gadidae) from western and eastern Greenland. Polar Biol 31:1017–1021
Krylov AA, Andreeva IA, Vogt C et al (2008) A shift in heavy and clay mineral provenance
indicates a middle Miocene onset of a perennial sea ice cover in the Arctic Ocean.
Paleoceanography 23:PA1S06. doi:10.1029/2007/PA001497
Lister AM, Climate change research group (2011) Natural history collections as sources of longterm datasets. TREE 26:153–154
Madsen ML, Fevolden S-E, Christiansen JS (2009) A simple molecular approach to distinguish
between two Arctic gadoid fishes Arctogadus glacialis (Peters, 1874) and Boreogadus saida
(Lepechin, 1774). Polar Biol 32:937–939
Mecklenburg CW, Møller PR, Steinke D (2011) Biodiversity of arctic marine fishes: taxonomy
and zoogeography. Mar Biodiv 41:109–140
Naish KA, Hard JJ (2008) Bridging the gap between the genotype and the phenotype: linking
genetic variation, selection and adaptation in fishes. Fish Fisheries 9:396–422
Nelson JS (2006) Fishes of the world, 4th edn. Wiley, New York
Patarnello T, Verde C, di Prisco G, Bargelloni L, Zane L (2011) How will fish that evolved at
constant sub-zero temperatures cope with global warming? Notothenioids as a case study.
Bioessays 33:260–268
Pärtel M, Szava-Kovats R, Zobel M (2011) Dark diversity: shedding light on absent species.
TREE 26:124–128
Perry AL, Low PJ, Ellis JR, Reynolds JD (2005) Climate change and distribution shifts in marine
fishes. Science 308:1912–1915
Pickard GL, Emery WJ (1990) Descriptive physical oceanography an introduction, 5th edn.
Butterworth-Heinemann, Oxford
Piepenburg D (2008) As time goes by: polar biology over the years 1982–2008. Polar Biol 32:3–7
Steffensen JF (2005) Respiratory systems and metabolic rates. In: Farrell AP, Steffensen JF (eds)
The physiology of polar fishes. Academic, New York, pp 203–238
Verde C, Lecointre G, di Prisco G (2006) The phylogeny of polar fishes and the structure,
function and molecular evolution of haemoglobin. Polar Biol 30:523–539
50
J. S. Christiansen
Verde C, Giordano D, Russo R, di Prisco G (2012) The adaptive evolution of polar fishes.
Lessons from the function of hemoproteins. In: di Prisco G, Verde C (eds) Adaptation and
evolution in marine environments—The impacts of global change on biodiversity, vol 1.
Series ‘‘From Pole to Pole’’. Springer, Berlin, pp 197–213
Walsh JE (2008) Climate of the Arctic marine environment. Ecol Appl 18:S3–S22
Ward RD, Hanner R, Hebert PDN (2009) The campaign to DNA barcode all fishes, FISH-BOL.
J Fish Biol 74:329–356
Whiteley NM, Christiansen JS, Egginton S (2006) Polar cod, Boreogadus saida (Gadidae), show
an intermediate stress response between Antarctic and temperate fishes. Comp Biochem
Physiol 145:493–501
Wienerroither R, Nedreaas KH, Uiblein F, Christiansen JS, Byrkjedal I, Karamushko O (2011)
The marine fishes of Jan Mayen Island, NE Atlantic—past and present. Mar Biodiv
41:395–411 doi: 10.1007/s12526-010-0055-y